Connect two load cell power supplies PFXA 401 signal

Fault tracking and troubleshooting: Connect two load cell power supplies VAC X X==UR=X39 X49 CPU PL 3 PL 2 PL 1 ribbon cable MC 400 (PFXA 401) X5 load cell signal PFVI 401 X load cell A1. If the matching device is correctly grounded at the installation site, it is not connected. D B A C black 11 blue matching unit A 5/25A 1.95 A load cell B D B C black 11 blue matching unit B 5/25A 1.95A Figure 28. The circuit diagram for a typical installation starts by performing a ‘main system test’.

Measure the resistance and insulation of the primary and secondary circuits. If no deviation is detected, check if the rolling mill frame is overloaded and if the weighing sensor is overloaded. If the load cell is overloaded, return it to the supplier for inspection, recalibration, and any necessary repairs. Overload may be caused by poor mechanical processing of the installation surface or dirt deposition between the load cell and the pressure plate.

With the continuous improvement of automation level in control, the requirements for operators are also constantly increasing, especially the technical requirements for DCS maintenance personnel are higher. How to effectively train relevant personnel, how to provide operators and DCS maintenance personnel with a systematic understanding of the entire DCS, is related to whether the role of DCS can be fully utilized. However, after the system is put into use, in order to ensure its safe and reliable operation, frequent experimental operations on the actual DCS are not allowed. Therefore, training based on the actual DCS is not practical, and simulation systems can solve this problem.

A simulation system is relative to a real DCS running in a process industrial system, which involves reproducing the real DCS in a non DCS computer system. Specifically, it is necessary to reproduce the complete distributed control system and even the simulation of on-site equipment as realistically as possible in computer information systems. Due to the fact that virtual DCS originates from real DCS, various operations and accidents that occur on real DCS can be verified on virtual DCS. Any control system configuration based on real DCS can be ported to run on simulation systems; Any control configuration debugged on a simulation system can also be ported to run on a real DCS system.

The DCS system is composed of three main parts: real-time data network XNET, human-machine interface station HMI connected to the network, and decentralized processing unit XCU. XCU is a hardware controller that faces the controlled object, performs fast data input and output processing and closed-loop control calculations, completes alarm detection, receives operation instructions, and configures modification instructions. HMI includes operator station, engineer station, historical data station, etc. Provide data to operators through flow charts, bar charts, curves, tables, buttons, dialog boxes, etc., interpret operation instructions, and send them to XCU. Through HMI, operators and engineers can intervene and modify the monitoring process, as well as complete data recording and statistics functions.

The composition of virtual DCS, like real DCS, is composed of decentralized control units (XCU), human-machine interfaces (HMI), and communication components. Virtual XCU is the core of virtual DCS. It refers to the porting of XCU functions from actual decentralized control units to virtual XCU software, which separates XCU functions from actual hardware. In this way, the entire virtual DCS system can work without hardware devices for data collection and computation.

On the premise of implementing the virtual control unit, establish a communication interface between the virtual control unit and the on-site device simulation model. After the simulation object composed of the on-site device simulation system is calculated, the state data of each model is transmitted to the virtual control unit VXCU through communication. After receiving data from the simulation system, the virtual XCU transmits the calculation results to the HMI for display, and at the same time transmits them to the simulation model to replicate the data control calculation function in the actual DCS.